Switch



1945- J. w. LAWSON Y 2,317,250

SWITCH Filed Feb. 1a, 1943 v U l IQVSNTOR v JOHN w. LAWSON I 6 1 y W/Mvfl HI: ATTORNEY Patented May 29, 1945 SWITCH John W. Lawson, Anderson, Incl, assignor to General Motors Corporation, Detroit, Mich., a corporation of Delaware Application February 18, 1943, Serial No. 476,262

4 Claims.

This invention relates to electric switches and particularly to switches which when used in an electrical system are normally closed and when opened render the system inoperative. Such a switch is generally known as a master switch in 5 33 insulate the contact 20 from the rod 30. a battery charging system for example, the switch Washer 34 is normally engaged by a shoulder 38 might be used to disconnect the battery. of the rod 30. The reduced portion 35 of rod or It is an object of the present invention to proplunger 30 which receives the non-conducting vide a master controlled switch which is closed parts 32, 33 and 34 is longer than the combined by a spring and is opened by pulling out a handle thickness of these parts; and contact 20 has a which, on being turned, cooperates with a memcentral hole slightly larger in diameter than the her so as to prevent reclosing of the switch by bushing 33. Therefore, there is a play between the spring when the handle is released. Through contact 20 and rod 30 so that the force carried the action of the spring, the handle cooperates downwardly by rod 30 will be distributed and with the member in such a way as to prevent contact will engage contacts 2| with substanaccidental turning of the handle in to such positially equal pressure. 7 tion that the spring can effect closing of the The case 23 is closed by cover 40 and sealed switch. by a gasket 4| having a central opening 42 for Further objects and advantages of the present receiving the rod and a tube 43 having a invention will be apparent from the following 20 flange 43a at itslower end joined to the cover 40 description, reference being had to the accomby welding for example. Within the tube 43, is panying drawing wherein a preferred embodisecured in any suitable manner a ring 44 from ment of the present invention is clearly shown. which extend two diametricall opposite lugs or In the drawing: keys 45 which project in parallelism axially of Fig. 1 is a plan view of a switch embodying the 5 the tube 43. Below the ring 44 are located a felt present invention. or leather Washer 46 and a metal washer 41.

Fig. 2 is a sectional view on line 2-2 of Fig. 1. A spring 50 surrounds the. rod 30 and is located Fig. 3 is an under side view of the handle of between the shoulder 5| of the rod 30 and the the switch shown in Figs. 1 and 2. Y 1 washers 41. Spring 50 urges the rod 30 down- Fig. 4 is a sectional view of the handle taken 0 wardly to cause the contact 20 normally to enon the line 44 of Fig. 3. gage the contacts 2|; and spring 50 urges the Fig. 5 is a sectional view of the handle taken felt washers 46 upwardly against the ring 44 to on the line 55 of Fig. 4. provide a dust-proof seal.

Fig. 6 is a plan view of that member of the The rod 30 is actuated by a handle 52 having switch with which the handle cooperates to prea central recess 53 provided with flats 54 covent accidental reclosing of the switch when the operating with flats 5-5 on opposite sides of rod handle is pulled out and turned. 30 so as to prevent relative rotary movement Fig. '7 is a sectional view on line l---! of Fig. 6. between handle 52 and rod 30 when these parts Fig. 8 is a bottom plan view of a modified form are secured together by a screw 56; therefore, of handle. accidental turning of screw 56 is prevented since Fig. 9 is a sectional view on line 9-9 of Fig. 8. handle 52 cannot be rotated relative to rod 30.

Fig. 10 is an end view looking in the direction Handle 52 has a skirt 5'! separated by space 58 of arrow 10 of Fig. 9. A portion of the skirt of from a hub 59, said space receiving the upper the handle being broken away. end of tube 43. The hub 59 is provided with Fig. 11 is a lan view of that member of the diametrically opposite recesses 60 for receiving switch with which the handle shown in Figs. 8, the lugs 45 of the ring 44 enclosed by tube 43. 9 and 10 will cooperate to prevent accidental re- The recess 60 is defined by surfaces 60a. Surclosing of the switch by the spring after the faces 6| extend from surfaces 60a to surfaces 62 handle has been pulled and turned. of recesses 63 defined in part by surfaces 64.

Fig. 12 is a sectional view on line l2-I2 of When the switch is closed, the recesses receive Fig. 11. e keys 45 provided by ring 44 (Fig. '7).

The switch comprises a movable contact 25 To open the switch, the handle 52is pulled out normally engaging fixed contacts2l provided by until the surfaces 60a of recesses 31! are located the head ends of terminal screws 22 which pass above the keys 45. Then the handle is turned through a case or housing 23 and are insulated in either direction so that the sides of the keys therefrom by washer 24 and strips 25 having ears 45 will engage diametrically opposite surfaces 34. 25a which align opposite side walls 23a of case thereby preventing further rotation of the handle 23 and guide the movements of the contact 20. 52. The handle 52 is then released so that the Contact 20 is insulatingly supported by rod 30 spring urges the handle downwardly so that the and is attached thereto by riveting over the rod 60 recess surfaces 62 engage the top ends 45a of keys at 30a to secure a metal washer 3| against a should 3| a of rod 30. In the normal position of contact 20, washer 3| is spaced from washer 32 which together with a washer 34 and a bushing 45 which are then received by the recesses 63. The surfaces 6| being lower than the surfaces 62, accidental turning of the handle 52 i prevented. To permit the closing of the switch, the handle 52 must first be pulled out until the surfaces BI are above the upper ends 45a of the keys 45; and the handle 52 is turned to cause the recesses 65 to register with the keys 45. The handle 52 is released to permit the spring 50 to force contact 20 into engagement with contacts 2|.

In the modified form of handle and ring shown in Figs. 9 through 12, the cooperating parts have been reversed that is those parts which were on the handle shown on Figs. 2, 3, 4 and are to be found in the ring I44 of Figs. 11 and 12 and to parts found in the ring 44 of Fig. '7 and to be found on the handle shown in Figs. 8, 9 and 10. The counterparts of keys 45 of ring 44 (Fig. 7) are the ribs I45 on the hub I59 of handle I522. The counterparts of the surfaces and recesses 60 through 64 of handle 52 are to be found at I60 through I64 as part of the ring I44. For example in Figs. 11 and 12, the recess I 60 of the ring I44 are the counterpart of the recesses Gil of the handle 52 (Figs. 3 and 4) While the embodiment of the present invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed i as follows:

1. A switch comprising; a case having a wall provided with an opening and carrying a sleeve about the opening, a. hollow member anchored within the sleeve; a handle having a body member extending into the sleeve, said members having slot and key portions adapted to register with each other when the handle is assembled with the sleeve to guide the handle axially of the sleeve for a predetermined distance, said slot and key portions being so arranged that the key portion will be free of the slot portion when the handle is moved outwardly a certain distance to allow the handle to rotate, said key portion cooperating with stops provided by the member provided with the slot portion to limit the rotation of the handle when said handle is rotated; and detent means adjacent the stop means provided by the member having said slot portion for receiving an end of the key portion to hold the handle in switch opening position and also prevent accidental turning of the handle, upon release of the handle; a rod fixed to and movable with the handle; resilient means for urging the rod inwardly; and relatively movable and fixed contacts caused to become engaged by movement of the rod inwardly.

2. In a switch, the combination comprising, a casing, a movable contact within the casing; a rod having one end connected to the contact; a sleeve about the other end of the rod and fixed to the casing; a handle for closing the open end of the sleeve and connected to the other end of the rod to actuate same, said handle having a depending boss extending into the sleeve, said boss being provided with stop means and notch means on its periphery and a detent means on its bottom; a spring supported within the sleeve and biasing the rod in one direction to urge the contact into closed position; a lug carried by the sleeve and extending into the notch of the boss for guiding the handle in a straight line movement upon manual operation of the handle to elevate the contact from its closed position to open position and to lift the notch beyond the lug whereby said handle may be rotated causing the top of the lug to engage stop means on the boss to limit rotary movements of the handle relative to the sleeve and causing the top of the lug to engage the detent means upon release of the handle to hold yieldingly the handle in an elevated position and thereby hold the contact in the open position, said lug and detent means operating to prevent accidental turning of the handle to such a position that the spring can effect moving of the contact into closed position.

3. A switch comprising in combination; a housing; stationary contacts and a movable contact mounted within the housing; a sleeve supported on the housing; a rod slidably and rotatably supported relative to the sleeve, said rod having one end extending into th housing and supporting the movable contact and having the other end connected to a handle; resilient means acting on said rod and 50 disposed as to transmit pressure for yieldingly maintaining the movable contact in engagement with the stationary conrtacts; a bushing fixed within the sleeve, interengaging provisions provided by the bushing and a boss provided by the handle for guiding the handle substantially in a'straight line movement, the construction and arrangement being such that, when the handle is moved outwardly to a point when the interengaging provisions are out of registry, the handle can be rotated against the tension of the resilient means while the contacts are in open relation; a stop provided by the bushing cooperating with the said mentioned provisions on the boss to limit the rotation of the handle; and interengaging means provided by the top of the bushing and the bottom of the boss for yieldingly maintaining the open relation of the contacts and to prevent accidental turning of the handle to such a position that the resilient means can effect movement of the movable contact into its normal position.

4. An electric switch including a casing, a tubular bearing supported relative to a wall of the casing; stationary contacts supported by the casing; bridge means operatively related to the contacts; a handle slidably supported by the bearing, said handle being provided with an opening; a rod connected to bridge means and the handle, said rod capable of rotating relative to the bridge means and non-rotatable with respect to the handle whereby movement of the handle will move the bridge means on the vertical; a lug extending upwardly from said bearing; means provided on said handle engageable with the cooperating means to hold the handle in an elevated position and hold the bridge means in an open position; a shoulder provided on said handle and engageable with the upper portion of the lug to limit the rotary movement of the handle when the handle is elevated a predetermined distance; recessed mean provided by the handle adjacent the shoulder adapted to receive the top of the lug and hold the handle in its elevated position and prevent the handle from turning; and resilient means disposed between the bearing and a flange carried by the rod for urging the rod inwardly to move the bridge means toward said contacts and the recessed means on the handle over the top of the lug whereby manual force will be necessary to turn the handle to allow the spring to move the handle and rod inwardly.

JOHN W. LAWSON. 

